Lights not triggering

The traffic lights controlling the dedicated left-turn lane at the first exit into Pontypridd, when coming off the northbound A470 slip road, do not appear to detect vehicles correctly. Specifically, when cars are waiting only in the dedicated left-turn lane (the left-most of the three lanes), the lights do not trigger a change. The signals only appear to activate when vehicles are present in the middle or right-hand lanes at this junction. This issue was observed at approximately 23:45 on 20/03/2026.